Cutting account identification (4)
I believe the answer is:
acid
'cutting' is the definition.
(I've seen this before)
'account identification' is the wordplay.
'account' becomes 'ac' (abbreviation).
'identification' becomes 'ID' (abbreviation).
'ac'+'id'='ACID'
(Other definitions for acid that I've seen before include "bad rain" , "Substance with pH of less than 7" , "It is neutralised by alkali" , "It turns litmus paper red" , "Bitter; biting" .)